US military veterans report very high levels of musculoskeletal (MSK) pain, including back pain, neck pain, and headache and have high rates of many mental health conditions, such as depression, anxiety, post-traumatic stress disorder (PTSD), often co-occurring with MSK pain. Veterans who have painful conditions often report high analgesic and prescription medication use, including opioids. The combination of MSK pain, mental health conditions, and frequent analgesic use is a rising concern in terms of disability, work productivity, quality of life and the risk of overuse and overdose from narcotics. Veterans often use complementary and alternative therapies (CAM), including chiropractic, for MSK complaints mental health concerns. However, few studies have addressed the role of chiropractic care for veterans within Veterans Health Administration (VHA) settings, or how such services might be integrated seamlessly into existing VHA clinical practice guidelines, physical and mental health screening and treatment programs or pain management approaches. To address this gap in health services, we propose a mixed-methods approach to develop integrative care pathways for the care of veterans with co-morbid musculoskeletal pain and anxiety, depression or PTSD. We will accomplish the following four Aims: Specific Aim 1: Develop an integrative care model that includes doctors of chiropractic in multidisciplinary teams treating patients with MSK pain and mental health co-morbidities in the VHA, based on the COCOA model; Specific Aim 2: Tailor existing chiropractic guidelines and best practices to interlink with current VHA pain management initiatives through a consensus building process; Specific Aim 3: Conduct a one-arm pilot clinical trial of this integrative care model including doctors of chiropractic in 20 veterans aged 55 and older with MSK pain and mental health co-morbidities to assess the feasibility, acceptability, safety, tolerability and target outcomes for future randomized controlled trial; Specific Aim 4: Revise the study protocol based upon pilot findings and submit a competitive research proposal for a fully-powered effectiveness study to NIH at the end of the study period. In summary, the Veterans Health Administration (VHA) has implemented progressive programs for both pain and mental health management. However, a gap exists in our knowledge of the effectiveness of integrative treatments including CAM added to existing pain management strategies for veterans with mental health co-morbidities. Chiropractic is one CAM treatment that has demonstrated its evidence of efficacy and safety in the treatment of MSK disorders, and the DoD/VA Pain Management Task Force comprehensive pain management program includes chiropractic as a Tier 1 treatment modality. However, the appropriate role for chiropractic in veteran populations, especially those with MSK pain and mental health disorders, requires further investigation.